公开(公告)号：US06438174B1

公开(公告)日：2002-08-20

申请号：US09147742

申请日：1999-06-04

申请人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

发明人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

IPC分类号： H04L512

CPC分类号： H04L5/006 ,  H04L1/0065 ,  H04L1/0071 ,  H04L5/0007 ,  H04L5/0046

摘要： A multi-carrier transmission system such as a DMT based VDSL system. The system uses orthogonal carriers with high order QAM constellations for the transmission of multiple bits per carrier and symbol. This estimate includes digital receiver and transmitter units with the receiver unit including a symbol detection unit. This system is adapted to determine a parameter for each single carrier with the parameter being indicative of a deviation of a received signal from a corresponding constellation point. It compares the parameter with an upper lower limit and if the parameter is outside the limits, changes the constellation used to modulate the carrier to a neighboring constellation. The symbol detection unit may be used to determine a parameter such as the ratio d2/&sgr;2, where d is the shortest distance between neighboring constellations, &sgr; is a standard deviation and &sgr;2 is the variance of the deviations of the input and output signal values of the symbol detection unit.

摘要翻译： 一种多载波传输系统，如基于DMT的VDSL系统。 该系统使用具有高阶QAM星座的正交载波，用于每个载波和符号的多个比特的传输。 该估计包括具有包括符号检测单元的接收器单元的数字接收器和发射器单元。 该系统适于确定每个单载波的参数，其中该参数指示接收到的信号与对应星座点的偏差。 它将参数与上限进行比较，如果参数超出限制，则将用于调制载波的星座更改为相邻星座。 符号检测单元可以用于确定诸如d2 / sigma2之类的参数，其中d是相邻星座之间的最短距离，σ是标准偏差，而sigma2是输入和输出信号值的偏差的方差 符号检测单元。

公开(公告)号：US06359926B1

公开(公告)日：2002-03-19

申请号：US09147748

申请日：1999-06-01

申请人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

发明人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

IPC分类号： H04L704

CPC分类号： H04L1/0025 ,  H04L1/0059 ,  H04L1/0071 ,  H04L27/2657 ,  H04L27/2662 ,  H04L27/2675

摘要： A two-way multi-carrier transmission system, such as a DMT system. If there are dynamic changes in the transmission parameters, synchronization must be maintained between the transmitter and the receiver when the transmission parameters changed. The first stage of such a process requires that the changes of parameter be notified by one transceiver to others involved in an active communication process over a slow transmission channel such as the control channel. Subsequently, the synchronization transceiver is adjusted simultaneously, i.e., from a predetermined DMT symbol. Such adjustments in time synchronization must be achieved with a minimum of overhead.

摘要翻译： 一种双向多载波传输系统，如DMT系统。 如果传输参数有动态变化，传输参数变化时，必须在发射机和接收机之间保持同步。 这种过程的第一阶段要求将参数的变化通过诸如控制信道的慢速传输信道由一个收发机通知参与有源通信过程中的其他人。 随后，同步收发器被同时调整，即从预定的DMT符号调整。 时间同步中的这种调整必须以最小的开销来实现。

公开(公告)号：US6160820A

公开(公告)日：2000-12-12

申请号：US147755

申请日：1999-06-14

申请人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

发明人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

IPC分类号： H04J11/00 ,  H04B3/00 ,  H04L27/26 ,  H04M3/00 ,  H04M11/00 ,  H04J1/00

CPC分类号： H04L5/006 ,  H04L5/0007 ,  H04L5/0037 ,  H04L5/0046

摘要： A multi-carrier transmission system, particularly a discrete multi-tone (DMT) system. Data is transmitted between two transceivers using a plurality of carriers. The frequency bandwidth of the system is divided between the plurality of carriers. The transmission system is adapted for operation in a heterogeneous network including a number of subscriber equipments having different channel characteristics and coexisting on the same cable. The length of cable for each subscriber terminal varies in relation to its respective location. The transmission system includes an allocation device for allocating the traffic of subscriber equipments having a shorter length of cable to tones starting from a higher frequency band of the system bandwidth.

摘要翻译： PCT No.PCT / SE97 / 01461 Sec。 371日期1999年6月14日第 102（e）1999年6月14日PCT PCT 1997年9月1日PCT公布。 出版物WO98 / 10556 日期1998年3月12日一种多载波传输系统，特别是离散多音（DMT）系统。 使用多个载波在两个收发器之间传输数据。 系统的频率带宽在多个载波之间划分。 传输系统适用于异构网络中的操作，包括具有不同信道特性的多个用户设备并且在同一电缆上共存。 每个用户终端的电缆长度相对于其各自的位置而变化。 传输系统包括分配装置，用于将具有较短电缆长度的用户设备的业务分配到从系统带宽的较高频带开始的音调。

公开(公告)号：US06625112B1

公开(公告)日：2003-09-23

申请号：US09147229

申请日：1999-03-11

申请人： Lennart Olsson ,  Gunnar Bahlenberg ,  Daniel Bengtsson ,  Siwert Hakansson ,  Anders Isaksson ,  Lars-Ake Isaksson ,  Mikael Isaksson ,  Magnus Johansson ,  Mauritz Lahti ,  Lis-Marie Ljunggren ,  Hans Lundberg ,  Tomas Nordstrom ,  Sven-Rune Olofsson ,  Tomas Stefansson ,  Hans Ohman ,  Goran Okvist

发明人： Lennart Olsson ,  Gunnar Bahlenberg ,  Daniel Bengtsson ,  Siwert Hakansson ,  Anders Isaksson ,  Lars-Ake Isaksson ,  Mikael Isaksson ,  Magnus Johansson ,  Mauritz Lahti ,  Lis-Marie Ljunggren ,  Hans Lundberg ,  Tomas Nordstrom ,  Sven-Rune Olofsson ,  Tomas Stefansson ,  Hans Ohman ,  Goran Okvist

IPC分类号： H04J1100

CPC分类号： H04L27/2662 ,  H04L27/2657 ,  H04L27/2672 ,  H04L27/2678

摘要： A mechanism for achieving frame synchronization in the frequency domain. In order to synchronize a receiver with a transmitter, on signal acquisition, the interval in which orthogonality exists is determined. Once this has been achieved, an argument function is calculated from the received frame. This argument function can then be used to improve the synchronization. This system is particularly suitable for use in ADSL and VDSL modems which can be used to give broad band access over copper networks. It is also relevant to broad band transmission in mobile and semi-mobile systems for transmission over radio channels.

摘要翻译： 实现频域帧同步的机制。 为了使接收机与发射机同步，在信号采集中，确定存在正交性的间隔。 一旦达到这个目的，就会从接收的帧中计算一个自变量函数。 这个参数函数可以用来改善同步。 该系统特别适用于ADSL和VDSL调制解调器，可用于通过铜网络实现宽带接入。 它也适用于通过无线电信道进行传输的移动和半移动系统中的宽带传输。

公开(公告)号：US06456649B1

公开(公告)日：2002-09-24

申请号：US09147743

申请日：1999-08-30

申请人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen ,  Per Odling

发明人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen ,  Per Odling

IPC分类号： H04B138

CPC分类号： H04L5/0046 ,  H04L1/0065 ,  H04L1/0071 ,  H04L5/0007 ,  H04L5/006

摘要： A multi-carrier transmission system such as a DMT system. Channel information is transmitted between two transceivers using a plurality of sub-carriers modulated with symbols, each of which represents a multiplicity of bits. Each of the transceivers includes a receiver and a transmitter in which a fixed maximum value was determined for the number of bits for each symbol and in which the system is adapted to determine the bit capacity per symbol of each of the plurality of sub-carriers and to increase the number of bits represented by a symbol transmitted over those sub-carriers having a capacity less than a fixed maximum value to the maximum value by the addition of channel coding bits. The fixed maximum value for the number of bits for each symbol may be determined on the basis of the bit capacity of that one of the sub-carriers having the highest theoretical bit capacity may be at least as large as the theoretical bit capacity.

摘要翻译： 诸如DMT系统的多载波传输系统。 信道信息在两个收发器之间使用多个用符号调制的子载波进行发送，每个子载波表示多个比特。 每个收发机包括接收机和发射机，其中确定每个符号的比特数的固定最大值，并且其中系统适于确定多个子载波中每个的每个符号的比特容量，以及 通过添加信道编码比特来将由具有小于固定最大值的容量的那些子载波发送的符号的比特数增加到最大值。 可以基于具有最高理论比特容量的一个子载波的比特容量可以至少与理论比特容量一样大来确定每个符号的比特数的固定最大值。

公开(公告)号：US06366554B1

公开(公告)日：2002-04-02

申请号：US09147759

申请日：1999-06-01

申请人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

发明人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

IPC分类号： H04J100

CPC分类号： H04L25/03159 ,  H04L1/0065 ,  H04L1/0071 ,  H04L5/0007 ,  H04L5/0046 ,  H04L5/0048 ,  H04L5/006 ,  H04L5/0094 ,  H04L25/0228 ,  H04L2025/0349 ,  H04L2025/037 ,  H04L2025/03802

摘要： A multi-carrier transmission system, for example a DMT system. Channel information is transmitted between two transceivers using a plurality of subcarriers. Each subcarrier, or symbol, has a parameter associated with it. The transceivers are adapted to transmit the channel information as a sequence of n groups in which each of the n groups contains information concerning the number of adjacent subcarriers which have the same value as the parameter, together with the actual value of the parameter. The parameter which may have a plurality of discrete values, may be a bit-loading value, or a QAM constellation identifier.

摘要翻译： 多载波传输系统，例如DMT系统。 使用多个子载波在两个收发器之间传送信道信息。 每个子载波或符号具有与其相关联的参数。 所述收发机适于发送所述信道信息作为n组的序列，其中，所述n个组中的每一个与所述参数的实际值一起包含与所述参数具有相同值的相邻子载波的数量的信息。 可以具有多个离散值的参数可以是位加载值或QAM星座标识符。

公开(公告)号：US06363128B1

公开(公告)日：2002-03-26

申请号：US09147746

申请日：1999-06-23

申请人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Håkansson ,  Ye Wen

发明人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Håkansson ,  Ye Wen

IPC分类号： H04L700

CPC分类号： H04L27/2675 ,  H04L27/2656 ,  H04L27/2657

摘要： A multi-carrier transmission system, such as a DMT system. A receiver must be able to recover a sampling clock that is very accurately synchronized to a transmitter sampling clock. Typically, synchronization is achieved by using a reserved carrier, the pilot carrier, which is transmitted with a fixed phase. The receiver sampling clock is then phase locked to the pilot carrier. Frame timing can be recovered by using a correlation technique. Thus an improved method of recovering a sample clock and phase locking the sampling clock to a pilot carrier is provided.

摘要翻译： 多载波传输系统，如DMT系统。 接收机必须能够恢复与发射机采样时钟非常准确同步的采样时钟。 通常，通过使用以固定相传输的保留载波，导频载波来实现同步。 接收机采样时钟然后被锁相到导频载波。 帧定时可以通过使用相关技术来恢复。 因此，提供了一种恢复采样时钟并将采样时钟锁相到导频载波的改进方法。

公开(公告)号：US20060209976A1

公开(公告)日：2006-09-21

申请号：US11436014

申请日：2006-05-17

申请人： Magnus Johansson ,  Lennart Olsson ,  Gunnar Bahlenberg ,  Daniel Bengtsson ,  Mikael Isaksson ,  Sven-Rune Olofsson ,  Sven Okvist

发明人： Magnus Johansson ,  Lennart Olsson ,  Gunnar Bahlenberg ,  Daniel Bengtsson ,  Mikael Isaksson ,  Sven-Rune Olofsson ,  Sven Okvist

IPC分类号： H04K1/10 ,  H04B1/10

CPC分类号： H04L25/03159 ,  H04L27/2655 ,  H04L2025/03414 ,  H04L2025/03522 ,  H04L2025/03617

摘要： In a multi-carrier system employing OFDM, for example DMT, an adaptive channel equalizer is normally used, operating in the frequency domain. The sampling clock is controlled so that the time delay between the transmitter and the receiver is effectively eliminated. If the information used to control the sampling clock is received from the equalized data stream, it will introduce an ambiguity between the operation of the channel equalizer and the mechanism used to control the sampling clock. Operation of the equalizer can mask an increasing time difference, between transmitter and receiver, which the sample clock controller should be tracking. The present invention eliminates the ambiguities in the operation of the equalizer and sample clock controller by preventing the equalizer accepting time differences which should be corrected by operation of the sample clock controller.

公开(公告)号：US06865232B1

公开(公告)日：2005-03-08

申请号：US09147750

申请日：1997-07-15

申请人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

发明人： Mikael Isaksson ,  Magnus Johansson ,  Harry Tonvall ,  Lennart Olsson ,  Tomas Stefansson ,  Hans Ohman ,  Gunnar Bahlenberg ,  Anders Isaksson ,  Goran Okvist ,  Lis-Marie Ljunggren ,  Tomas Nordstrom ,  Lars-Ake Isaksson ,  Daniel Bengtsson ,  Siwert Hakansson ,  Ye Wen

IPC分类号： H04L1/00 ,  H04L25/03 ,  H04L27/26 ,  H04L27/34 ,  H04K1/10 ,  H04L27/28

CPC分类号： H04L1/0025 ,  H04L1/0059 ,  H04L1/0071 ,  H04L5/0007 ,  H04L5/0046 ,  H04L5/006 ,  H04L25/03159 ,  H04L27/2656 ,  H04L27/2657 ,  H04L27/2662 ,  H04L27/3461 ,  H04L2025/03414 ,  H04L2025/03522

摘要： A multi-carrier transmission system has a plurality of transceivers, each having a receiver and a transmitter. Data is transmitted between the transceivers by modulating the data onto a multiplicity of carrier waves in the form of multi-bit symbols, wherein each carrier wave constitutes a channel, and wherein the number of bits per symbol (the bit loading), varies between channels and, within a channel, with time, so that each channel has associated therewith a bit loading parameter. In operation, the multi-carrier system is adapted to synchronously update, at the transceivers, the bit loading parameters associated with each channel by transmission of data over a control channel, in that the control channel is established, at system start-up, on a predetermined one of the multiplicity of carrier waves whose identity is known to the transceivers, and in that the control channel is, after start-up, changed from the predetermined channel to a further channel, selected by the first transceiver on the basis of channel characteristics.

摘要翻译： 多载波传输系统具有多个收发机，每个收发机具有接收机和发射机。 通过以多位符号的形式将数据调制到多个载波上，在收发器之间传输数据，其中每个载波构成一个信道，并且其中每个符号的比特数（比特加载）在信道之间变化 并且在频道内，随着时间，使得每个频道与其相关联地加载参数。 在操作中，多载波系统适于在收发机处通过控制信道上的数据传输来同步更新与每个信道相关联的比特加载参数，因为在系统启动时建立控制信道 多个载波的预定的一个载波，其身份对于收发机是已知的，并且控制信道在启动之后从预定信道改变到由第一收发信机基于信道选择的另一个信道 特点

公开(公告)号：US06751261B1

公开(公告)日：2004-06-15

申请号：US09147230

申请日：1999-02-09

申请人： Lennart Olsson ,  Gunnar Bahlenberg ,  Daniel Bengtsson ,  Siwert Håkansson ,  Anders Isaksson ,  Lars-Ake Isaksson ,  Mikael Isaksson ,  Magnus Johansson ,  Mauritz Lahti ,  Lis-Marie Ljunggren ,  Hans Lundberg ,  Tomas Nordstrom ,  Sven-Rune Olofsson ,  Tomas Stefansson ,  Hans Oman ,  Goran Okvist

发明人： Lennart Olsson ,  Gunnar Bahlenberg ,  Daniel Bengtsson ,  Siwert Håkansson ,  Anders Isaksson ,  Lars-Ake Isaksson ,  Mikael Isaksson ,  Magnus Johansson ,  Mauritz Lahti ,  Lis-Marie Ljunggren ,  Hans Lundberg ,  Tomas Nordstrom ,  Sven-Rune Olofsson ,  Tomas Stefansson ,  Hans Oman ,  Goran Okvist

IPC分类号： H04L506

CPC分类号： H04L27/2662 ,  H04L27/2657 ,  H04L27/2672 ,  H04L27/2678

摘要： With OFDM systems the frequency domain data is the Fourier transform of the received time domain OFDM frames. The time domain frames must be sampled, at the receiver, in synchronism with the transmitter, so that each received frame contains data from only a single transmitted frame. It is vital for this synchronism to be maintained in order to maintain the orthogonality of the frames. A typical multi-carrier system, of the OFDM type, which uses a cyclic prefix permits orthogonality to be maintained when there is a small deviation from exact frame synchronisation. Because the signalling interval includes both an entire frame and the cyclic prefix, which is a repetition of part of the frame, a frame sampled within the signalling interval will contain data from only one frame. Since the signalling interval is greater than the frame period, this gives some leeway in frame alignment. In a multi-carrier system of the OFDM type, an adaptive channel equalizer, operating in the frequency domain, is often used. The internal parameters in such an equalizer contain, in addition to information about the characteristics of the channel, information which can be interpreted as the time deviation between the sampling clocks of the transmitter and the receiver. The present invention utilizes this information to control the sampling clock of the receiver in a more robust way than has previously been possible with known techniques. The present invention is particularly suitable for use in ADSL and VDSL modems which can be used to give broadband access over copper networks. The invention is also of relevance to broadband transmission in mobile and semi-mobile systems for transmission over the radio channels.

摘要翻译： 对于OFDM系统，频域数据是接收的时域OFDM帧的傅里叶变换。 必须在接收机处与发射机同步地采样时域帧，使得每个接收的帧包含来自仅一个发射帧的数据。 为了保持帧的正交性，保持该同步是至关重要的。 使用循环前缀的OFDM类型的典型多载波系统当与精确帧同步的偏差很小时，允许维持正交性。 由于信令间隔包括作为帧的一部分的重复的整个帧和循环前缀，所以在信令间隔内采样的帧将仅包含来自一个帧的数据。 由于信令间隔大于帧周期，所以在帧对齐中给出了一些余地。 在OFDM类型的多载波系统中，经常使用在频域中工作的自适应信道均衡器。 除了关于信道特性的信息之外，这种均衡器中的内部参数还包含可被解释为发射机和接收机的采样时钟之间的时间偏差的信息。 本发明利用该信息以比先前已知技术可能的更可靠的方式来控制接收机的采样时钟。 本发明特别适用于ADSL和VDSL调制解调器，可用于通过铜网络提供宽带接入。 本发明还涉及用于在无线电信道上传输的移动和半移动系统中的宽带传输。